Your RunIQ should be cleaned periodically. Fingerprints can be removed from the watch face with a dry microfiber cloth, but if your RunIQ has a lot of caked on dirt, you can use products that are formulated for electronic displays (like computer monitors)--always avoiding harsh cleaning products that you would normally find under the kitchen or bathroom sink.
Cleaning the strap can be done with with a damp cloth, too. For best results, remove the watch bands before cleaning them.
The back of your watch can get dirty, which can affect the charging ports and the heart rate monitor. Avoid harsh chemicals and use a damp cloth to remove the bulk of the dirt, then a microfiber cloth to dry. You can use a cotton swab to clean any debris from the charging contacts (the 4 circles on the top of the back of the watch) and to clear any remaining dirt from the heart rate monitor (the 3 squares in the middle of the back of the watch). Remember to dry these areas before putting your RunIQ back on your wrist.